Ha, a Muscovy Duck - there is a town in England, Ely, where they are almost overrun with these; I believe the original ones escaped from a private collection and they bred, and bred! You have captured the ugliness wonderfully here, and displayed the duck well against the oof background.
These guys are indeed quite weird looking. You kinda feel sorry for 'em, but I suspect to each other they're really quite handsome! Excellent job of showing the detail. (I lived in an apartment for a short while, and these guys lived in the pond there. One day I came home, went inside, and a few minutes later there was a knock at my door. It was three of these guys. They literally knocked. Apparently the former tenant fed them every evening!)
Wow, I'm sure there is some sort of dermatologist that can help this guy! Nice picture, excellent DOF, with nice facial detail. The shadow on the chest, and the hot spot near the nare are the only "criticism" I have. Did you use a fill flash? 6